diff options
Diffstat (limited to 'udev/udevsettle.c')
| -rw-r--r-- | udev/udevsettle.c | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/udev/udevsettle.c b/udev/udevsettle.c new file mode 100644 index 0000000000..cb63a66bba --- /dev/null +++ b/udev/udevsettle.c @@ -0,0 +1,178 @@ +/* + * Copyright (C) 2006 Kay Sievers <kay@vrfy.org> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation version 2 of the License. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * + */ + +#include <stdlib.h> +#include <stddef.h> +#include <string.h> +#include <stdio.h> +#include <unistd.h> +#include <errno.h> +#include <dirent.h> +#include <fcntl.h> +#include <syslog.h> +#include <getopt.h> +#include <sys/stat.h> +#include <sys/types.h> + +#include "udev.h" +#include "udevd.h" + +#define DEFAULT_TIMEOUT 180 +#define LOOP_PER_SECOND 20 + +static void print_queue(const char *dir) +{ + LIST_HEAD(files); + struct name_entry *item; + + if (add_matching_files(&files, dir, NULL) < 0) + return; + + printf("\n\nAfter the udevadm settle timeout, the events queue contains:\n\n"); + + list_for_each_entry(item, &files, node) { + char target[NAME_SIZE]; + size_t len; + const char *filename = strrchr(item->name, '/'); + + if (filename == NULL) + continue; + filename++; + if (*filename == '\0') + continue; + + len = readlink(item->name, target, sizeof(target)); + if (len < 0) + continue; + target[len] = '\0'; + + printf("%s: %s\n", filename, target); + } + + printf("\n\n"); +} + +int udevsettle(int argc, char *argv[], char *envp[]) +{ + char queuename[PATH_SIZE]; + char filename[PATH_SIZE]; + unsigned long long seq_kernel; + unsigned long long seq_udev; + char seqnum[32]; + int fd; + ssize_t len; + int timeout = DEFAULT_TIMEOUT; + int loop; + static const struct option options[] = { + { "timeout", 1, NULL, 't' }, + { "help", 0, NULL, 'h' }, + {} + }; + int option; + int rc = 1; + int seconds; + + logging_init("udevsettle"); + udev_config_init(); + dbg("version %s\n", UDEV_VERSION); + sysfs_init(); + + while (1) { + option = getopt_long(argc, argv, "t:h", options, NULL); + if (option == -1) + break; + + switch (option) { + case 't': + seconds = atoi(optarg); + if (seconds > 0) + timeout = seconds; + else + fprintf(stderr, "invalid timeout value\n"); + dbg("timeout=%i\n", timeout); + break; + case 'h': + printf("Usage: udevadm settle [--help] [--timeout=<seconds>]\n\n"); + goto exit; + } + } + + strlcpy(queuename, udev_root, sizeof(queuename)); + strlcat(queuename, "/" EVENT_QUEUE_DIR, sizeof(queuename)); + + loop = timeout * LOOP_PER_SECOND; + while (loop--) { + /* wait for events in queue to finish */ + while (loop--) { + struct stat statbuf; + + if (stat(queuename, &statbuf) < 0) { + info("queue is empty\n"); + break; + } + usleep(1000 * 1000 / LOOP_PER_SECOND); + } + if (loop <= 0) { + info("timeout waiting for queue\n"); + print_queue(queuename); + goto exit; + } + + /* read current udev seqnum */ + strlcpy(filename, udev_root, sizeof(filename)); + strlcat(filename, "/" EVENT_SEQNUM, sizeof(filename)); + fd = open(filename, O_RDONLY); + if (fd < 0) + goto exit; + len = read(fd, seqnum, sizeof(seqnum)-1); + close(fd); + if (len <= 0) + goto exit; + seqnum[len] = '\0'; + seq_udev = strtoull(seqnum, NULL, 10); + info("udev seqnum = %llu\n", seq_udev); + + /* read current kernel seqnum */ + strlcpy(filename, sysfs_path, sizeof(filename)); + strlcat(filename, "/kernel/uevent_seqnum", sizeof(filename)); + fd = open(filename, O_RDONLY); + if (fd < 0) + goto exit; + len = read(fd, seqnum, sizeof(seqnum)-1); + close(fd); + if (len <= 0) + goto exit; + seqnum[len] = '\0'; + seq_kernel = strtoull(seqnum, NULL, 10); + info("kernel seqnum = %llu\n", seq_kernel); + + /* make sure all kernel events have arrived in the queue */ + if (seq_udev >= seq_kernel) { + info("queue is empty and no pending events left\n"); + rc = 0; + goto exit; + } + usleep(1000 * 1000 / LOOP_PER_SECOND); + info("queue is empty, but events still pending\n"); + } + +exit: + sysfs_cleanup(); + logging_close(); + return rc; +} |